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Effects of the Coptidis Rhizoma Extract on the Membranous Nephropathy induced by Cationic Bovine Serum Albumin in Mice (황연(黃連)이 Cationic Bovine Serum Albumin 투여로 유발된 Membranous Nephropathy Mouse Model에 미치는 영향)

  • Chae, Eun-Young;Cho, Chung-Sik;Kim, Cheol-Jung
    • The Korea Journal of Herbology
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    • v.24 no.1
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    • pp.99-110
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    • 2009
  • Objectives : The current treatment regimens for patients with nephrotic syndrome due to membranous nephropathy(MN) are based on steroids or immunosuppressive therapy with the aim of reducing proteinuria and improving outcome. Although these treatments attenuate the deterioration of renal function in MN patients, it has been suggested that all are burdened by significant toxicity. Therefore, more specific and less toxic therapies are needed. This study was to evaluate the effects of Coptidis Rhizoma Extract(CRE) on the MN induced by cBSA in mice. Methods : Mice were divided into 4 groups. One group named for 'Normal' was injected with a saline solution not to be immunized. The rest groups were treated as follows; After mice were immunized with 0.2 mg of cBSA and Freund's complete adjuvant one time every two weeks for 6 weeks, they received intra-peritoneal injection of 10 mg/kg of cBSA daily for 4 weeks. Also, they were divided into 3 groups. The first named for 'Control' was not given CRE. The second for 'CRE-250' was given oral administration of 250 mg/kg of CRE daily for 4 weeks. The third for 'CRE-500' was given 500 mg/kg of CRE. All of mice were sacrificed 4 weeks after the first immunization. We measured a body weight and 24hrs proteinuria as well as serological analysis. The morphologic changes of renal glomeruli were also observed with a light microscope and an electron microscope. Results : The levels of 24 hrs proteinuria, triglyceride, IgG, IL-6 were significantly decreased in both CRE groups. And the level of IgM was significantly decreased in CRE-250 group. In histological findings of kidney tissue, thickening of GBM and deposition of electron-density were consideraly decreased in both CRE groups. Conclusions : The present study suggests that CRE is highly effective when treating mice with MN induced by cBSA. More clinical data and studies are to be done for efficient application.

Study on collapse mechanism and treatment measures of portal slope of a high-speed railway tunnel

  • Guoping Hu;Yingzhi Xia;Lianggen Zhong;Xiaoxue Ruan;Hui Li
    • Geomechanics and Engineering
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    • v.32 no.1
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    • pp.111-123
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    • 2023
  • The slope of an open cut tunnel is located above the exit of the Leijia tunnel on the Changgan high-speed railway. During the excavation of the open cut tunnel foundation pit, the slope slipped twice, a large landslide of 92500 m3 formed. The landslide body and unstable slope body not only caused the foundation pit of the open cut tunnel to be buried and the anchor piles to be damaged but also directly threatened the operational safety of the later high-speed railway. Therefore, to study the stability change in the slope of the open cut tunnel under heavy rain and excavation conditions, a 3D numerical calculation model of the slope is carried out by Midas GTS software, the deformation mechanism is analyzed, anti-sliding measures are proposed, and the effectiveness of the anti-sliding measures is analyzed according to the field monitoring results. The results show that when rainfall occurs, rainwater collects in the open cut tunnel area, resulting in a transient saturation zone on the slope on the right side of the open cut tunnel, which reduces the shear strength of the slope soil; the excavation at the slope toe reduces the anti-sliding capacity of the slope toe. Under the combined action of excavation and rainfall, when the soil above the top of the anchor pile is excavated, two potential sliding surfaces are bounded by the top of the excavation area, and the shear outlet is located at the top of the anchor pile. After the excavation of the open cut tunnel, the potential sliding surface is mainly concentrated at the lower part of the downhill area, and the shear outlet moves down to the bottom of the open cut tunnel. Based on the deformation characteristics and the failure mechanism of the landslides, comprehensive control measures, including interim emergency mitigation measures and long-term mitigation measures, are proposed. The field monitoring results further verify the accuracy of the anti-sliding mechanism analysis and the effectiveness of anti-sliding measures.

Analysis of Research Trends in Information Literacy Education Using Keyword Network Analysis and Topic Modeling (키워드 네트워크 분석과 토픽모델링을 활용한 정보활용교육 연구 동향 분석)

  • Jeong-Hoon, Lim
    • Journal of the Korean Society for information Management
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    • v.39 no.4
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    • pp.23-48
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    • 2022
  • The purpose of this study is to investigate the flow of domestic information literacy education research using keyword network analysis and topic modeling and to explore the direction of information literacy education in the future. For this reason, 306 academic papers related to information literacy education published in academic journals of the library and information science field in Korea were chosen. And through the preprocessing process for abstracts of the paper, total keyword appearance frequency, keyword appearance frequency by period, and keyword simultaneous occurrence frequency were analyzed. Subsequently, keyword network analysis analyzed the degree centrality, between centrality, and eigenvector centrality of keywords. Using structural topic modeling analysis, 15 topics -curriculum, information literacy effect, contents of information literacy education, school library education, information media literacy, information literacy ability evaluation index, library anxiety, public library program, health information literacy ability, digital divide, library assisted instruction improvement, research trend, information literacy model, and teacher role-were derived. In addition, the trend of topics by year was analyzed to confirm the change in relative weight by topic. Based on these results, the direction of information literacy education and the suggestions for follow-up research were presented.

Personalized Speech Classification Scheme for the Smart Speaker Accessibility Improvement of the Speech-Impaired people (언어장애인의 스마트스피커 접근성 향상을 위한 개인화된 음성 분류 기법)

  • SeungKwon Lee;U-Jin Choe;Gwangil Jeon
    • Smart Media Journal
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    • v.11 no.11
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    • pp.17-24
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    • 2022
  • With the spread of smart speakers based on voice recognition technology and deep learning technology, not only non-disabled people, but also the blind or physically handicapped can easily control home appliances such as lights and TVs through voice by linking home network services. This has greatly improved the quality of life. However, in the case of speech-impaired people, it is impossible to use the useful services of the smart speaker because they have inaccurate pronunciation due to articulation or speech disorders. In this paper, we propose a personalized voice classification technique for the speech-impaired to use for some of the functions provided by the smart speaker. The goal of this paper is to increase the recognition rate and accuracy of sentences spoken by speech-impaired people even with a small amount of data and a short learning time so that the service provided by the smart speaker can be actually used. In this paper, data augmentation and one cycle learning rate optimization technique were applied while fine-tuning ResNet18 model. Through an experiment, after recording 10 times for each 30 smart speaker commands, and learning within 3 minutes, the speech classification recognition rate was about 95.2%.

Optimizing Locations for Micro-mobility Parking Area based on User Big-data Analysis (빅데이터 기반 공유형 마이크로 모빌리티의 주차시설 입지 최적화 연구)

  • Choi, Nakhyeon;Kim, Junghwa
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.2
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    • pp.195-206
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    • 2023
  • Most of the Micro-mobility parking in Korea use Dockless system. However, Dockless can result in cluttering, infrastructure deficiencies, and safety challenges as has been observed in cities. It is necessary to introduce a Station Parking system in order to solve the drawbacks of the dockless, but the introduction without engineering has low accessibility and induces side effects. In this study, to decide optimal location about number of the Micro-mobility Station, we has been applied the MCLP model about the coverage range, usage demand, usage time in order to classify the type of Micro-mobility Station. For the MCLP, User Date input to reflect realistic demand in Bundang new town, Korea. The result show that the optimal number of facilities in 400 m was 146, and the coverage ratio was 99.83 %, which was most suitable coverage for solving the parking problem. We also classified the demand into 4 levels and the usage time into 3 levels, and by crossing them, we were able to classify the Parking lot types into 12 types. It is possible to propose strategic policies in the installation and operation of Micro-mobility Parking System.

A Study on Improvement of Safety Management by Port Stevedoring Industry (항만하역업 안전관리 개선방안에 관한 연구)

  • Min-Seop SIM;Jeong-Min Lee;Do-Yean KIM;Yul-Seong Kim
    • Journal of Navigation and Port Research
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    • v.47 no.1
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    • pp.37-48
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    • 2023
  • Recently, the increase of international trade volume is leading to risk exposure and safety accidents in the port terminal industry. In addition, as Serious Disaster Punishment Act came into effect on January, 2021, various guidelines and laws to protect safety and life in port terminals are being enacted. However, despite these efforts, medium-to-large safety accidents in the port terminal industry have occurred. According to the Korea Occupational Safety and Health Agency, from 2016 to 2019, the number of casualties in the port handling industry increased by 4.2%. To build some effective follow-up management of port accidents and preparation of related safety laws/systems, a risk analysis in consideration of causes and damage of accidents should be conducted. Therefore, in this study, major risk factors and preventive measures were derived by conducting risk assessment based on 1,039 cases of port terminal accidents collected by the Korea Occupational Safety and Health Agency for five years. Priorities for preventive measures were then determined through IPA analysis, Borich needs analysis, and The Locus For Focus analysis.

An Evaluation Technique for the Path-following Control Performance of Autonomous Surface Ships (자율운항선박의 항로추정성능 평가기법 개발에 관한 연구)

  • Daejeong Kim;ChunKi Lee;Jeongbin Yim
    • Journal of Navigation and Port Research
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    • v.47 no.1
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    • pp.10-17
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    • 2023
  • A series of studies on the development of autonomous surface ships have been promoted in domestic and foreign countries. One of the main technologies for the development of autonomous ships is path-following control, which is closely related to securing the safety of ships at sea. In this regard, the path-following performance of an autonomous ship should be first evaluated at the design stage. The main aim of this study was to develop a visual and quantitative evaluation method for the path-following control performance of an autonomous ship at the design stage. This evaluation technique was developed using a computational fluid dynamics (CFD)-based path-following control model together with a line-of-sight (LOS) guidance algorithm. CFD software was utilized to visualize waves around the ship, performing path-following control for visual evaluation. In addition, a quantitative evaluation was carried out using the difference between the desired and estimated yaw angles, as well as the distance difference between the planned and estimated trajectories. The results demonstrated that the ship experienced large deviations from the planned path near the waypoints while changing its course. It was also found that the fluid phenomena around the ship could be easily identified by visualizing the flow generated by the ship. It is expected that the evaluation method proposed in this study will contribute to the visual and quantitative evaluation of the path-following performance of autonomous ships at the design stage.

Modeling of algal fluctuations in the reservoir according to the opening of Yeongju Dam (영주댐 개방에 따른 호내 조류 변동 모의)

  • Lee, Dong Yeol;Kim, Seong Eun;Baek, Kyong Oh
    • Journal of Korea Water Resources Association
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    • v.56 no.3
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    • pp.173-184
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    • 2023
  • Due to climate change, algal blooms frequently occur not only in Korea but also around the world, and the risk of toxicity of harmful algae has recently been issued. It is known that the representative harmful algae, cyanobacteria, are caused by the intersection of three factors: water temperature, residence time, and nutrients. In this study, water quality simulation was carried out using EFDC, a three-dimensional numerical model, to analyze the variations in water quality due to the decrease of residence time according to the opening of Yeongju Dam in Naeseong-Cheon. In fact, the concentration of chlorophyll-a in Yeongju Dam in the summer of 2021 was significant, exceeding the 'algae warning' for a long time based on the previous algae warning system. On the other hand, as a result of performing the simulation under the condition that the dam gate was completely opened, the concentration of chlorophyll-a was mostly reduced below the 'algae warning' level during the simulation period. It was confirmed that reducing the residence time by restoring the flow of Naeseong-Cheon is a way to immediately reduce algae in Yeongju Dam.

Determining Groundwater-surface Water Interaction at Coastal Lagoons using Hydrogeochemical Tracers (수리화학적 환경 추적자를 이용한 강원도 석호지역에서의 지하수-지표수 상호작용에 대한 연구)

  • Dong-Hun Kim;Jung-Yun Lee;Soo Young Cho;Hee Sun Moon;Youn-Young Jung;Yejin Park;Yong Hwa Oh
    • Journal of Soil and Groundwater Environment
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    • v.28 no.2
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    • pp.1-11
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    • 2023
  • Groundwater-surface water interaction was evaluated using water quality parameters (temperature and electrical conductivity), distributions of stable water isotopes (δ2H and δ 18O), and Rn-222 in lagoon water, groundwater, and seawater at three coastal lagoons (Songji (SJ), Youngrang (YR), and Sunpo (SP) Lagoon) in South Korea. From the results of composition and distributions of δ2H and δ18O, it was found that groundwater fraction of lagoon water in YR Lagoon (76%) was slightly higher than those of SJ (42%), and SP (63%) Lagoon. Based on Rn-222 mass balance model, groundwater discharge into SJ Lagoon in summer 2020 was estimated to be (3.2±1.1)×103 m3 day-1, which showed a similar or an order of magnitude higher than the results of previous studies conducted in coastal lagoons. This study can provide advanced techniques to evaluate groundwater-surface water interaction in coastal lagoons, wetlands, and lakes, and help to determine the effects of groundwater on coastal ecosystems.

The Effect of Failure of Online Food Delivery Service Recovery Strategies on Consumer Attitude and Behavioral Intention: Focusing on Justice Theory (온라인 음식 배달 서비스 회복 전략의 실패가 소비자 태도 및 행동 의도에 미치는 영향: 공정성 이론(Justice Theory)을 중심으로)

  • Jungkun Park;Sangwoo Lee;Hyowon Hyun;Jihwan Yum
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.161-180
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    • 2023
  • This study empirically analyzed the effect of perceived injustice on service recovery measures proposed by online food delivery service (OFDS) companies on consumer disappointment. This study adopted interaction justice, information justice, procedural justice, and distributive justice as sub-variables of justice perception based on the justice theory. In addition, the differences by generation (MZ generation and other generations) were examined in the relationship between negative word-of-mouth behavior and switching intentions due to service recovery failure. An online survey was conducted targeting 250 adult consumers in the U.S for the empirical analysis of this research model. The results of the data analysis demonstrated that negative perceptions about the procedural justice and distributive justice among the service recovery strategies had a positive effect upon the consumer's disappointment. Furthermore, it was confirmed that the consumer's disappointment due to the perceived injustice of the service recovery strategy had a positive effect on the consumer's negative word-of-mouth behavior and switching intentions. The verification results of the moderation effect in the relationship between negative word-of-mouth behavior and switching intention, it was found that the younger the age(MZ generation), the higher the possibility of causing dysfunctional behavior. This study expands the scope of related research by presenting a new perspective on the justice perception in the service recovery process by verifying dysfunctional behavior of consumers caused due to the failure of the service recovery strategy. It is believed that the results of this study will be used as basic data for the establishment of practical strategies for OFDS companies to prevent double defection of their customers.